摘要
采用含Ag50%～68%、Cu10%～30%、Zn12%～20%、Sn0%～10%的银基钎料,通过激光钎焊,改变钎焊有效热输入(激光输出功率和钎焊时间),研究了TiNi形状记忆合金与不锈钢异质钎焊接头的微观组织和性能.结果表明:AgCuZnSn钎料对TiNi形状记忆合金和不锈钢的润湿性较好,钎焊接头界面平整、致密,与TiNi形状记忆合金形成的界面反应层较窄,而与不锈钢形成的界面反应层较宽.钎焊有效热输入对TiNi形状记忆合金热影响区组织和性能影响较大.钎焊有效热输入量过高,将导致TiNi形状记忆合金侧热影响区组织晶粒粗大、硬度降低、 塑性提高.严格控制钎焊工艺参数可以获得具有较高抗拉强度、形状记忆效应和超弹性的TiNi形状记忆合金与不锈钢钎焊接头.
TiNi shape memory alloy(TiNi SMA) is brazed to stainless steel(SS) by using silver-based filler metal with Ag 50%-68%, Cu 10%-30%, Zn 12%-20% and Sn 0%-10% and by means of laser welder. The microstructures and properties of brazing joint are studied by means of adjusting technological parameters(laser output power and brazing time). The results showed that the AgCuZnSn filler metal is good for the wettability to brazing TiNi SMA and SS. Joint interface between filler metal and TiNi SMA is smooth and compact. A reaction layer is formed between filler metal and SS. There are important influences of brazing technological parameters on the microstructures and properties of TiNi SMA heat affected zone. The higher effective heat input will result in grain growth, hardness reducing and plasticity increasing in the heat affected zone of TiNi SMA. The high joint tensile strength, shape memory effect and superelasticity could be obtained by strictly controlling brazing technological parameters.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2005年第2期132-136,共5页
Journal of Mechanical Engineering
基金
吉林省自然科学基金资助项目(20000518)
关键词
TINI形状记忆合金
不锈钢
钎焊
组织
性能
TiNi shape memory alloy Stainless steel Brazing Microstructures Properties
